1. Field of the Invention
The present invention relates to a management tool for reviewing historical data and performing forecasting simulations relating to pollutant emissions from power plants and the like.
2. Description of Related Art
Stricter limitations on the amounts of pollutants and so called greenhouse gases have necessarily made pollutant emissions a controlling factor in management decisions regarding the operation of electric power plants. Power generated by burning fossil fuels leads to the production of the oxides of nitrogen, collectively referred to as NOx. In addition, sulfurous compounds are emitted into the air by coal burning power plants. All fossil fuel burning power plants produce carbon monoxide (CO) and carbon dioxide (CO2) as byproducts of the combustion process. Carbon monoxide is produced due to incomplete combustion of hydrocarbons, is toxic, and is generally produced in lesser amounts than CO2. Carbon dioxide, while not toxic itself, has been implicated as a cause of global warming due to the greenhouse effect.
Restrictions on the amounts of the aforementioned substances that may be emitted are prescribed by law and are enforced by governmental agencies. The power plant manager has several options in reducing the emission rate of these pollutants in order to comply with existing regulations. The rate of emission of all these pollutants can be reduced by reducing the overall power output of the plant. The overall power output of the plant can be reduced, and thus the pollutant output, can be reduced by planned outages and/or by purchasing power from elsewhere. Emission of sulfurous compounds such as SO2 can be reduced by using gas scrubbers and/or by changing fuels from high sulfur coal to low sulfur coal or oil. Emission of nitrogen oxides can additionally be mitigated by operational changes affecting efficiency and/or combustion conditions of the power plant, by changing fuel types, and by installing Selective Catalytic Reduction (SCR) equipment. Increasing the proportion of air to fuel can help mitigate CO emissions. The emission of CO2 can additionally be reduced by increasing the efficiency of the power generation process such that less fuel has to be burned for each megawatt of electricity generated. The efficiency of the power generation process can be increased by using technologies such as cogeneration and waste heat recovery.
With so many choices facing the power plant or electric utility manager in the effort to meet the cap on pollutant emissions, it becomes difficult for the manager to pick the right strategy or combination of strategies to maximize the profit to the electric utility while complying with the limits on the emission of pollutants. The need exists for a management tool that allows the electric utility manager to forecast the company's profit for every available strategy and combination of strategies for complying with the limits on pollutant emissions, and then to select the pollution control scheme that yields the maximum profit to the utility. In addition, it would be desirable for such a tool to use real time data to automatically update the input parameters to the decision making process and revise the forecasted outcomes for the various strategies considered. Such a tool would of necessity, given the voluminous amount of data that need to be processed and the need for automatic and continuous updates, have to be implemented at least in part using a computer system. Although computer implemented management system have been proposed in the art, as evidenced by the references cited below, none of the references is seen to address the problem of finding the optimum pollution control strategy for an electric power generating plant.
U.S. Pat. No. 3,775,592, issued to Masahisa Ando et al. on Nov. 27, 1973, is related to a feedback process control system. The system of Ando et al. uses pattern recognition wherein the coordinates defined by the process output specify a point on the pattern. Control signals are generated as a function of the nature of the specified point on the pattern.
U.S. Pat. No. 4,628,462, issued to Richard E. Putman on Dec. 9, 1986, is related to a control system for a cogeneration power plant which controls the power output to match the actual demand. The system of Putman does not deal with the simulation of future pollutant emissions.
U.S. Pat. No. 5,063,506, issued to John C. Brockwell et al. on Nov. 5, 1991, is related to a computerized cost optimization system for minimizing the cost of supplying parts. The computer calculates the cost of a particular supply method such as air freight, ocean freight, land freight, on site storage, and warehouse storage, and the computer then presents the results to a user.
U.S. Pat. No. 5,548,528, issued to James D. Keeler et al. on Aug. 20, 1996, is related to a virtual sensor that can function as a pollutant sensor when the actual sensor is down so as to provide uninterrupted monitoring of pollution emission. The Keeler et al. system uses a stored model of the plant and measured control inputs to the plant to generated a virtual pollution sensor output to the control system of the plant. The keeler et al. system does not generate forecasts of future pollutant emissions based on projected demand for power generation.
U.S. Pat. No. 5,712,985, issued to Michael D. Lee et al. on Jan. 27, 1998, is related to a computerized demand forecasting and production scheduling system for forecasting the demand for a particular business item.
U.S. Pat. No. 5,797,129, issued to Drius Rohan on Aug. 18, 1998, is related to a computerized control system for a multi-resource, multi-task environment where at least one resource is shared between tasks. The system of Rohan can be used to schedule tasks for optimal resource usage and elimination of bottlenecks.
U.S. Pat. No. 5,826,238, issued to Wen-Lin Chen et al. on Oct. 20, 1998, is related to a method and system for operating a data base computer system and a resource allocation computer for allocating resources within a manufacturing plant.
U.S. Pat. No. 5,826,040, issued to Hugh E. Fargher et al. on Oct. 20, 1998, is related to a method for planning the production schedule within a factory. Each job is divided into a plurality of processing segments and the segments are processed in accordance to a fuzzy set algorithm.
U.S. Pat. No. 5,845,258, issued to Brian M. Kennedy on Dec. 1, 1998, is related to a computer based planning system where a plan is compared to system behavior and then the plan is adjusted according to a selected strategy.
U.S. Pat. No. 5,890,133, issued to Michael Ernst on Mar. 30, 1999, is related to a computer based method for dynamic optimization of business processes. The Method of Ernst uses parameters, process data and result data and uses stored data to identify a business process having propitious result data. The method of Ernst then requires that the parameters be modified according to the business process having propitious result data and the actual results to be verified subsequent to the modification of the parameters.
Canadian Patent Number 959169, issued to Jerry R. McIntyre et al. on Dec. 10, 1974, is related to a computer based method for calculating the fractions of various products within the product stream from a gas well in order to properly price the product stream as a function of the composition of the product stream and the market price of the product stream's various fractions.
None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed.